I'm getting mad - sixth memory stick dead in Mac Pro 2008

Micron is making the most horrible memories I've ever seen. Out of 8 stick 6 are dead.

So far other failed sticks were replaced with Micron (the same model), Kingston , Qimonda, Hynix, Nanya. Almost huge collection of different brands working together I think I'm only missing Elixir, FCM, GoodRAM and CSX

Now I'm going to get cheap Qimonda sticks with large heatsinks (for the first time) and we will see how these will perform...

Micron is making the most horrible memories I've ever seen. Out of 8 stick 6 are dead.

So far other failed sticks were replaced with Micron (the same model), Kingston , Qimonda, Hynix, Nanya. Almost huge collection of different brands working together I think I'm only missing Elixir, FCM, GoodRAM and CSX

Now I'm going to get cheap Qimonda sticks with large heatsinks (for the first time) and we will see how these will perform...

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This is the first time you've gotten ones with the correct Heat Sinks?

Pretty sure this is why the heat sinks aren't a suggestion, they're a requirement...

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Not really. In my 1,1 I had two sticks with "slim" heatsinks and two with half big / half small heatsinks for several years. Despite the temperature being around 70-80 Centigrades on the slim ones I got not one single hiccup, even when running full load for several consecutive days (and nights)!

Not really. In my 1,1 I had two sticks with "slim" heatsinks and two with half big / half small heatsinks for several years. Despite the temperature being around 70-80 Centigrades on the slim ones I got not one single hiccup, even when running full load for several consecutive days (and nights)!

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If they can't work with small heatsinks then in 1U servers there should be fire

I've added some additional copper heatsinks on a core of a FB-DIMM chip, but this dropped temps only a little bit.

If they can't work with small heatsinks then in 1U servers there should be fire

I've added some additional copper heatsinks on a core of a FB-DIMM chip, but this dropped temps only a little bit.

It's time to start thinking about Mac Pro 2009

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Servers are often much noisier. Given that you weren't using something that was certified, there's no way to guarantee that it will work. It shouldn't have taken 6 sticks to figure that out. As for the 2009, they fixed refurb pricing. In the US hex core machines have come up around $2450. You should understand that things are cooled differently in a rackmount server.

I replaced my Apple RAM with Memory America modules that have the full size heat sinks. In 4 years of running at 80 degrees 2 modules have gone bad out of 8. In each case the vendor has replaced all 4 sticks from the set containing the bad module with 2 matched pairs at postage cost only.
Lifetime warranties FTW.

I dunno, but I purchased several sticks from DMS back in 2008 with big honking heat sinks and have never had an issue. In fact I don't think I've had a problem with their certified stuff since I started buying memory from them in the 90s.

The only memory modules I've ever had die (3 in total) are the "official" Apple ones that came with the Pro. The ones I've bought from OWC have been rock solid. A bit sad really that Apple couldn't have done better with their choice of manufacturer.

If they can't work with small heatsinks then in 1U servers there should be fire

I've added some additional copper heatsinks on a core of a FB-DIMM chip, but this dropped temps only a little bit.

It's time to start thinking about Mac Pro 2009

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Umm, a server generally has large fans that push a lot of air thru them. The Mac Pros on the other hand are designed to sit next to a desk where noise from large fans are generally not tollerated. There's a big difference between servers and workstations. I know that seems crazy..... (or not)

Not really. In my 1,1 I had two sticks with "slim" heatsinks and two with half big / half small heatsinks for several years. Despite the temperature being around 70-80 Centigrades on the slim ones I got not one single hiccup, even when running full load for several consecutive days (and nights)!

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Also the 1,1 only uses 667mhz RAM and runs a lot cooler than the 800mhz Ram in the 3,1's. Also, it has been shown that for 512mb and 1GB sticks, the temperatures remain low enough that the slim heat sinks aren't as big of a deal but once you step up to 2GB and especially 4GB, they become even more necessary.

Also the 1,1 only uses 667mhz RAM and runs a lot cooler than the 800mhz Ram in the 3,1's.

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Not sure about that one. 800MHz is 20% more, granted - but i would expect the temperatures to only increase nonlinear, as the producers should have experience in fabrication after producing 667MHz for some time (thus better quality dies from the process) and therefore allowing for 800MHz in the first place. Depending on the module there might even have been a die-shrink somewhere along the way.

With a linear increase we would be talking about 80 degrees plus 20%, thus getting close to 100°C, which i can't believe to be tolerated by neither the producer nor the purchaser, as the failure rate would probably skyrocket on such modules.

Also, it has been shown that for 512mb and 1GB sticks, the temperatures remain low enough that the slim heat sinks aren't as big of a deal but once you step up to 2GB and especially 4GB, they become even more necessary.

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Not according to my experiences: The slim heatsinks were sitting on the 4GB modules, whereas the 2GB modules had the half/half ones. And neither made any problems, despite the 78-80°C on the slim heatsink ones.

Pretty sure this is why the heat sinks aren't a suggestion, they're a requirement...

Click to expand...

Just curious (new to the "light" side of the force), but why are mac pro's so much more demanding on their RAM. I've built many a PC and always thought heatsinks on ram was just a gimmick, and never had any problems using non-heatsink sticks.

Not according to my experiences: The slim heatsinks were sitting on the 4GB modules, whereas the 2GB modules had the half/half ones. And neither made any problems, despite the 78-80°C on the slim heatsink ones.

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Here's some good information on user experiences using the slim heat sinks vs apple recommended....

Just curious (new to the "light" side of the force), but why are mac pro's so much more demanding on their RAM. I've built many a PC and always thought heatsinks on ram was just a gimmick, and never had any problems using non-heatsink sticks.

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You've probably never built a PC with FBDIMMS which is what the 1,1 - 3,1 Mac Pros use. The ABM chip on them get super hot and requires a lot of cooling. Regularly unbuffered, non-ecc RAM wouldn't have an ABM chip and therefore requires limited cooling.

4Rx8 sticks does not work in Mac Pro 2008 :/ I have to return them, but the good news is I've used some compressed air on my Micron stick and BOOM it's fully working again ! It was just a lot of dust under the heatsink.

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